Joint



April 23, 1940. J. H. JACOBSON JOINT Filed June 6, 1938 PIC-3.2.

FIG.

FIG. 6.

FIG.5.

FIG.4.

MOVEMENT OVE ME NT INVENTOR JAMES H. JACOBSON.

HIS ATTORNEY.

Patented Apr. 23, 1940 1 UNITED STATES PATENT OFFICE 14 Claims.

' My invention relates to the construction of bridges, masonry and concrete structures, and particularly tov the building of concrete pavements, and more particularly to an improved type of expansion joint which bridges the space between and connects the adjoining end faces of the adjacent concrete slabs and makes'provision for both the linear and vertical movement thereof while sealing the space there-between against the infiltration of water and dirt.

The primary objects of my present invention are to provide a connection between the elements comprising the joint, whereby each may move independently of the other, but still retain their cooperative relations to efi'ect the flexing of the seal and simultaneously compensate for the movements of the adjoining slabs;

To provide for the relative vertical movement between the end faces of the adjoining slabs as occasioned by the imposed vehicular load and impact;

.To aiford facilities for sealing and cushioning Y the connection between the elements comprising the joint;

To obtain a prefabricated sealing member with a capping or armor of rubber or comparable material prior to the assembly of the joint structure and its initial installation in the slab;

To reduce the possibility of fatigue destroying or fracturing the metal forming the sealing member;

To facilitate and provide for the assembly of a sealing member either between two precast slabs, or as in patch work or where one slab is poured subsequent to the pouring of the adjoinway slab; and

To position ap'ortion of the seal of the joint below the anchoring extension to form an interlock and positive water tight seal.

My present invention has these and other objects, all of which will be apparent to those skilled in the art and may be more readily understood when read in conjunction with the accompanying drawing (one sheet) which illustrates a preferred embodiment of my invention, it being manifest that changes and modifications may be resorted to without departure from the spirit of the claims forming a part hereof.

In the drawing:

Fig, 1 is a vertical section through the ends of a pair of adjoining concrete slabs with my joint assembly shown bridging the space therebetween;

Fig.7 2 is a similar fragmentary view illustrating one modification which comprises the ofiset in the anchoring end sections of the seal and a preformed cap;

Fig. 3 is a similar View of the seal assembled to a piece of rubber or saturated felt strip, which takes the place of the air cushion stool of Fig. 1;

Fig. 4 is an enlarged fragmentary sectional detail of the interlock seam shown assembled to the intermediate connecting section of the seal with one anchoring end section;

Fig. 5 is a like view showing the relative vertical movement made possible between the anchors and the intermediate connecting section of the seal; and

Fig. 6 is a view similar to Fig. 4 and Fig. 5, showing in dotted lines the relative lateral movement made possible by this type of a seam.

Similar reference characters refer to similar parts throughout the several views. v

The structure illustrated involves the specific application of one form of my invention to a roadway slab. For purposes of description only, I choose to so define my invention as applied to this particular construction; however, I wish it understood that my invention is equally effective when adopted or used in any poured or precast structure, whether it be a roadway slab, retaining wall, swimming pool, reservoir, canal lining, warehousefloor, dock, industrial plant, sidewalk, driveway, airport runway, bridge, etc., for as a matter of fact, it is applicable to an almost unlimited number of structures. And while I describe my invention in its preferred embodiment, it is to be further understood that the words which I use are words of description and not of limitation.

Joints of this type, that is, air-cushioned or metallic sealed joints as they are termed, have been in use for many years. Their performance has been very carefully checked under changing climatic conditions and under the application of varying loads. It has been found that whereas dowel bars or similar mechanical devices are used" for the express purpose of preventing and controlling the relative vertical movement of the ends of the joined slabs, still there does exist considerable movement due to the elasticity of the concrete itself and the clearance of the bridg-' ing member such as the dowel bar, and that when heavy loads are carried across the joined ends of the slabs, a relative vertical movement is set up whichis far greater than just vibration, in

used for this purpose.

fact this movement is found to be so great that the seal of the joint becomes crystallized and the metal reaches its fatigue point and gradually disintegrates.

My invention now consists in spanning the space intervening between the adjoining end faces of adjacent concrete slabs I0 and II, with an air cushion type metallic joint comprising a stool member having side walls I2-l2 connected at the bottom with the base I3, and at the top with a seal I4, thus forming an envelope having side walls and connecting top and bottom walls. The envelope is reinforced with a metallic spacer I5 to prevent its premature collapse during installation and also carries a plurality of spaced dowel bars as shown at I6, positioned mid-depth of the slab and extending back into each slab as shown for the specific purpose of effecting a positive load transfer from one slab to the next adjoining.

The top of each side wall l2 of the joint or stool member, is formed outwardly into gutters or wings I! upon which the sealing member as a unit I4 is mounted. The sealing element itself comprises opposing anchoring end-sections Iii-I8 and a flexible intermediate connecting section I9 of the general shape of an inverted U, the anchoring sections I8 being provided with intermittent apertures I8 throughout their length so that the concrete in its plastic state may form a bond through the anchor elements of the end sections and thereby become permanently affixed to the concrete slabs and go and come with the movement of each slab respectively. The intermediate-connecting section I9 is flexibly aifixed to each anchoring end section I8 by means of a movably sealed, cushioned and interlocked seam as shown, wherein each anchoring element is formed upwardly at 29 and then downwardly and beaded at 2|, the intermediate connecting section having complemental parts formed upwardly at 22 and likewise beaded at 23. The interlock seam thus formed in itself is not a tight or pressed seam. On the contrary, it provides for a loose sliding fit so that the intermediate connecting section l9 may move independently and relative to the anchoring extensions I8 as indicated in dotted lines in Figs. 5 and 6 of the drawing. The drawing carries the legend Movement for the purpose of illustration. This detail is presented to show what is meant by relative movement between the anchor members and the intermediate connecting section of the metallic seal.

To efiect a positive water tight connection between the members I8 and I9 of the metallic seal, I provide a resilient filler 24 which may be composed or rubber, asphalt or any of the well known combinations or tar products commonly The filler extends across the top of the member I9 and down along the sides of this member and is in direct contact with the end face of each slab as shown (Fig. 1) and when poured flows into the interlocking seam and forms a film or cushion between the elements comprising the seam as shown specifically in Fig. 4 of the drawing; or the seam itself may be painted with a similar product before assembly.

The type of interlocking seam illustrated serves another purpose. It is common practice today to build the anchoring elements and the intermediate or connecting element of the seal in one piece, and to secure this one piece seal to the stool of the joint by means of a key or connecting member so that if the joint itself is deformed as it takes the cambre to conform to the crown of the road, these elements move in regards to one another, thus preventing their collapse or distortion. My invention now permits the anchoring elements I8 themselves to be permanently afiixed to the stool as shown and the intermediate connecting section of the seal I9 may then slide in relation to the anchoring sections I8, to effect this purpose.

As a modification of the details expressed in Fig. l of the drawing, I have illustrated a construction shown in Fig. 2 whereby the side walls of the joint I2I2 are offset at 25 forming a recessinto which the anchoring elements I8 of the seal which are provided with a complemental offset 26, and the resilient capping 32, extend down into the recess as at 21. In building a structure as here illustrated, it is my purpose to preform or precast the resilient or rubber capping 32; so that it may be replaced from time to time should occasion arise.

Such a construction further makes it possible to vulcanize or otherwise afiix the rubber cap-' ping 32 to the seal member I9 prior to its installation so that the member I9 with the attached capping 32 may be affixed to the anchors I8I8 after the anchors I8 I8 have been permanently installed in the slab.

As a further illustration of the applicability of my invention, I have shown at Fig; 3 the assembly of my seal to a piece of preformed joint such as an asphalt plank or saturated felt, rubber or cork filler member 30, the anchors of the seal being shown formed inwardly at 3I to grip the strip 30' and thus provide for complete rigid assembly prior to'installation. i

The foregoing discussion and the illustrations shown on the accompanying drawing describe my invention as applied in general to poured concrete cast in situ; and, whereas I have not shown the specific structure, I wish it understood that my invention is equally applicable to precast concrete, art marble, imitation stoneQglas's, terra cotta and other similar products or combinations thereof.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A seal for bridging and closing a gap between the adjoining end faces of spaced-apart slabs and providing for the relative movement of the slabs, said seal comprising opposed anchoring end portions and an intermediate connecting portion, each of said end portions being adapted to be secured to its respective slab, and said intermediate portion being affixed to each end portion, each means of afiixment consisting of a pair of relatively loose-fitting complemental parts comprising a substantially U-shaped member carried by the intermediate connecting portion of the seal, and a substantially inverted U-shaped member carried by the adjacent anchoring end portion of the seal, each upstanding leg of each U-shaped member entering the inverted U of its respective anchoring end portion and spaced therefrom to provide for the.

relative movement of the respective slabs.

2; A seal as per claim 1, wherein the means of affixment of the intermediate portion of the seal to its respective end portions consists of an interlocked seam wherein the relatively reversed leg of each U-shaped member enters the complement of the other and is spaced from the walls thereof to provide for relative movement 1 spective end portions comprising the U-shaped members consists in the -U-shaped members being formed from the material of the intermediate portion,' and the inverted U-shaped members being formed from the material of each respective anchoring end portion of the seal.

4. A seal as per claim 1, which includes a bead formed on the free end of each U-shaped member and which bead is adapted to be enclosed Within its complemental inverted U-shaped member.

5. A seal as per claim 1, which includes a resilient cap for said seal, said cap having a portion thereof adapted to extend over said intermediate connecting portion of said seal and between the end faces of the adjoining slabs.

6. A seal as per claim 1, which includes a resilient cap for said seal, said cap having a portion thereof adapted to extend over said intermediate connecting portion of said seal and another portion of said cap adapted to be positioned between said intermediate connecting portion of said seal and the end face of its respective slab.

7. A seal as per claim 1, which includes a load-transfer member bridging the gap between the end faces of the adjoining slabs adapted to limit the relative movement of the respective slabs and thereby limit the relative movement between said intermediate connecting portion of said seal and the respective anchoring end portions of said seal.

8. A seal as per claim 1, which includes a support for said seal prior to and during the pouring 0f the spaced slabs, said support adapted to be positioned in the gap between the adjoining end faces of the slabs, and said seal being secured to said support.

9. A seal as per claim 1, which includes a support for said seal positioned within the gap between the adjoining end faces of the spacedapart slabs, a portion of said support being adapted to extend into and be confined within the walls of said seal to reinforce said seal against premature collapse during the pouring of the plastic concrete.

10. A sealing element for bridging and sealing the space between the adjoining end faces of adjacent concrete slabs providing for both the relative vertical and linear movement thereof, said sealing element comprising a member for connecting the adjoining slabs, said member having opposed anchoring end sections and a flexible intermediate connecting section adapted to be located in the space between the end faces of the slabs, said intermediate connecting section being hingedly afiixed to each anchoring end section, the means of afiixment consisting of a pair of loose-fitting complemental parts com prising a substantially U-shaped member on the intermediate connecting section of said sealing element and a substantially inverted U-shaped member on the adjacent anchoring end section, one upstanding leg of the U-shaped member of the connecting section entering the inverted U of the anchoring section and being spaced therefrom, said hinged connection by means of a movably sealed, cushioned, and interlocked seam providing for the relative movement of the slabs, and each of said anchoring end sections being adapted to be rigidly and permanently secured to the respective end face of its adjacent-concrete slab.

11. An element for sealing the space between the adjoining end faces of adjacent concrete slabs and providing for the relative movement thereof, said sealing element comprising a member for connecting the adjoining slabs, said member having opposed anchoring end sections and an intermediate connecting section adapted to be located in the space between the end faces of the slabs, said intermediate connecting section being affixed to each anchoring end section by means of an interlocked seam providing for relative movement between said anchoring sections and said intermediate connecting section, said interlocked seam comprising a pair of loosetting complemental parts consisting of substantially U-shaped members, the leg of each member entering the complement of the other and being spaced therefrom providing room for 'each' to vmove within the other.

12. A member for sealing the space between vthe adjoining end faces of adjacent concrete slabs and providing for the relative movement thereof, said sealing member being adapted to connect the adjoining slabs, said member having.

inverted U-shaped member forming part of said anchoring end section, the upstanding leg of said U-shaped member of the intermediate section entering and spaced from thewalls of the inverted U-shaped member of the anchoring end section, and a resilient cap for said sealing member, said cap having one portion extending over said intermediate connecting section and another portion adapted to be located between the faces of said slabs and said connecting section of said sealing member.

13. A joint for sealing the space between the adjoining end faces of adjacent concrete slabs and providing for the relative movements thereof, said joint comprising a seal and a stool for supporting the seal, said'seal being adapted to connect the adjoining slabs and being comprised of opposed anchoring end sections and an intermediate connecting section adapted to be located in the space between the end faces of the slabs. said intermediate connecting section being affixed to each anchoring end section by means of an interlocked seam consisting of a pair of loose fitting complemental parts comprising a substantially U-shaped member forming part of said intermediate section and a substantially inverted U-shaped member forming part of said anchoring end section, the upstanding leg of said U-shaped member of the intermediate section entering and spaced from the walls of the inverted U-shaped member of the anchoring end.

section, and a resilient cap for said seal, said cap having one portion extending over said intermediate connecting section and another portion adapted to be located between the faces of said slabs and said connecting section of said seal.

14. A joint for concrete slab construction comprising a joint member for positioning between adjacent slabs and a load transfer member bridging the space between the slabs, said joint member comprising means for sealing the space between the slabs and a support for said sealing means, said sealing means being hingedly affixed to the faces of said slabs, said sealing means 71 comprising an intermediate flexible portion and an anchoring portion, the means of affixment consisting of a pair of loose-fitting complemental parts comprising a substantially U-shaped memmember of the connecting section entering the 5 inverted U of the anchoring section and being spaced therefrom, said hinged connection.

JAMES H. JACOBSON. 

